Climate Insights for San José

The climate in San José is hot. The average annual temperature is 27°C and approximately 1272mm of precipitation falls per year. September is the wettest month, receiving around 223mm of rainfall. San José is in the Northern Hemisphere. Summer begins at the end of June and lasts through September. The summer months are: May, April, August. The coldest months are January, February, December, when temperatures can drop to 19°C.

San José sees moderate temperature variation throughout the year, ranging from 19°C to 37°C. May is the hottest month, with daytime highs reaching 37°C and an average of 30°C. January is the coolest month, with minimum temperatures around 19°C and an average of 24°C. On average, daily temperatures fluctuate by about 10°C between overnight lows and afternoon highs. The sharpest temperature change occurs between February and March, with a 2°C shift in average temperatures.

San José is a fairly wet location, receiving approximately 1272mm of precipitation annually, which averages out to around 106mm per month. The wettest month is September, averaging 223mm of rainfall. June and October also tend to see above-average precipitation. The driest month is February, with just 27mm. That's 196mm less than September, the wettest month. Rainfall is heavily concentrated in certain months, creating a distinct wet and dry season. Visitors should plan around these patterns, as the difference between peak and low months is dramatic.

San José is mildly breezy, with an average annual wind speed of 13km/h. For context, sustained winds below 12km/h are generally light, while anything above 25km/h is considered strong. The windiest month is April, averaging 16km/h, though still comfortable for most outdoor activities. The calmest conditions occur in October, with average winds dropping to 10km/h, making it an ideal period for wind-sensitive activities. There is moderate seasonal variation in wind speed, with a 6km/h gap between the calmest and windiest months.

It is currently spring in San José, which began on March 20, 2026. San José is in the Northern Hemisphere, where spring begins in March, summer in June, autumn in September, and winter in December. The warmest period peaks in May at around 37°C, while the coldest stretch bottoms out in January near 19°C. Summer is next, beginning on June 21, 2026 — 89 days from now.

The best time to visit San José is during January, February and December, when the weather is most comfortable for travellers. During these months, average temperatures hover around 24°C with modest rainfall averaging 44mm per month. By contrast, May can be uncomfortably hot with temperatures reaching 37°C. A light rain jacket is recommended, though showers are generally brief and shouldn't disrupt your plans.

The table below shows monthly climate averages for San José based on historical weather data. Min and max temperatures represent typical overnight lows and afternoon highs for each month, shown in degrees Celsius (°C). Precipitation is measured in millimetres (mm) and indicates the average total rainfall per month. Wind speed is the average sustained speed in kilometres per hour (km/h). All values are based on averages from over 10 years of historical weather data. The current month is highlighted for quick reference.